Lenze 8400 BaseLine D - Manual (Page 237)

Lenze · 8400 BaseLine D · Reference manual · DMS 5.5 EN · 01/2014 · TD05
237
10 Function library
10.3 L_PCTRL_1
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
10.3.2 Ramp function generator
The PID output is led via a ramp function generator with linear characteristic. This serves to transfer
setpoint step-changes at the PID output into a ramp which should be as steep as possible.
[10-4] Acceleration and deceleration times
• t
ir
and t
if
are the desired times for changing between w1 and w2.
• The ramps for acceleration and deceleration can be set individually.
• C227 : Acceleration time T
ir
• C228 : Deceleration time T
if
• The t
ir
/t
if
values are converted into the required Ti times according to the following formula:
• The ramp function generator is immediately set to "0" by setting bInAct to TRUE.
10.3.3 Operating range of the PID process controller
The value range of the input signal nSet_a and thus the operating range of the PID process controller
can be limited with the following parameters:
• C231/1 : Pos. maximum (default setting: 199.9 %)
• C231/2 : Pos. minimum (default setting: 0.0 %)
• C231/3 : Neg. minimum (default setting: 0.0 %)
• C231/4 : Neg. maximum (default setting: 199.9 %)
10.3.4 Evaluation of the output signal
After the limitation, the output signal is evaluated with the influencing factor nInflu_a. The evalu-
ation is activated/suppressed along a ramp when the input bEnableInfluenceRamp is set to TRUE.
The ramp times are set with the parameters "Acceleration time influence" ( C243 ) and "Deceleration
time influence" ( C244 ).
w1, w2 = change of the main setpoint as a function of t
ir
and t
if
RFG-OUT = output of the ramp function generator
RFG-OUT
100 %
w2
w1
t
0 %
t
ir
t
ir
T
ir
T
ir
T
ir
t
ir
100 %
w2 w1 –
----------------------- ⋅ = T
if
t
if
100 %
w2 w1 –
----------------------- ⋅ =